1 /* BFD back-end for PPCbug boot records.
2    Copyright (C) 1996-2016 Free Software Foundation, Inc.
3    Written by Michael Meissner, Cygnus Support, <meissner@cygnus.com>
4 
5    This file is part of BFD, the Binary File Descriptor library.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program; if not, write to the Free Software
19    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 
23 /* This is a BFD backend which may be used to write PowerPCBug boot objects.
24    It may only be used for output, not input.  The intention is that this may
25    be used as an output format for objcopy in order to generate raw binary
26    data.
27 
28    This is very simple.  The only complication is that the real data
29    will start at some address X, and in some cases we will not want to
30    include X zeroes just to get to that point.  Since the start
31    address is not meaningful for this object file format, we use it
32    instead to indicate the number of zeroes to skip at the start of
33    the file.  objcopy cooperates by specially setting the start
34    address to zero by default.  */
35 
36 #include "sysdep.h"
37 #include "safe-ctype.h"
38 #include "bfd.h"
39 #include "libbfd.h"
40 
41 /* PPCbug location structure */
42 typedef struct ppcboot_location
43 {
44   bfd_byte	ind;
45   bfd_byte	head;
46   bfd_byte	sector;
47   bfd_byte	cylinder;
48 } ppcboot_location_t;
49 
50 /* PPCbug partition table layout */
51 typedef struct ppcboot_partition
52 {
53   ppcboot_location_t	partition_begin;	/* partition begin */
54   ppcboot_location_t	partition_end;		/* partition end */
55   bfd_byte		sector_begin[4];	/* 32-bit start RBA (zero-based), little endian */
56   bfd_byte		sector_length[4];	/* 32-bit RBA count (one-based), little endian */
57 } ppcboot_partition_t;
58 
59 /* PPCbug boot layout.  */
60 typedef struct ppcboot_hdr
61 {
62   bfd_byte		pc_compatibility[446];	/* x86 instruction field */
63   ppcboot_partition_t	partition[4];		/* partition information */
64   bfd_byte		signature[2];		/* 0x55 and 0xaa */
65   bfd_byte		entry_offset[4];	/* entry point offset, little endian */
66   bfd_byte		length[4];		/* load image length, little endian */
67   bfd_byte		flags;			/* flag field */
68   bfd_byte		os_id;			/* OS_ID */
69   char			partition_name[32];	/* partition name */
70   bfd_byte		reserved1[470];		/* reserved */
71 }
72 #ifdef __GNUC__
73   __attribute__ ((packed))
74 #endif
75 ppcboot_hdr_t;
76 
77 /* Signature bytes for last 2 bytes of the 512 byte record */
78 #define SIGNATURE0 0x55
79 #define SIGNATURE1 0xaa
80 
81 /* PowerPC boot type */
82 #define PPC_IND 0x41
83 
84 /* Information needed for ppcboot header */
85 typedef struct ppcboot_data
86 {
87   ppcboot_hdr_t	header;				/* raw header */
88   asection *sec;				/* single section */
89 } ppcboot_data_t;
90 
91 /* Any bfd we create by reading a ppcboot file has three symbols:
92    a start symbol, an end symbol, and an absolute length symbol.  */
93 #define PPCBOOT_SYMS 3
94 
95 #define ppcboot_set_tdata(abfd, ptr) ((abfd)->tdata.any = (ptr))
96 #define ppcboot_get_tdata(abfd) ((ppcboot_data_t *) ((abfd)->tdata.any))
97 
98 /* Create a ppcboot object.  Invoked via bfd_set_format.  */
99 
100 static bfd_boolean
ppcboot_mkobject(bfd * abfd)101 ppcboot_mkobject (bfd *abfd)
102 {
103   if (!ppcboot_get_tdata (abfd))
104     {
105       bfd_size_type amt = sizeof (ppcboot_data_t);
106       ppcboot_set_tdata (abfd, bfd_zalloc (abfd, amt));
107     }
108 
109   return TRUE;
110 }
111 
112 
113 /* Set the architecture to PowerPC */
114 static bfd_boolean
ppcboot_set_arch_mach(bfd * abfd,enum bfd_architecture arch,unsigned long machine)115 ppcboot_set_arch_mach (bfd *abfd,
116 		       enum bfd_architecture arch,
117 		       unsigned long machine)
118 {
119   if (arch == bfd_arch_unknown)
120     arch = bfd_arch_powerpc;
121 
122   else if (arch != bfd_arch_powerpc)
123     return FALSE;
124 
125   return bfd_default_set_arch_mach (abfd, arch, machine);
126 }
127 
128 
129 /* Any file may be considered to be a ppcboot file, provided the target
130    was not defaulted.  That is, it must be explicitly specified as
131    being ppcboot.  */
132 
133 static const bfd_target *
ppcboot_object_p(bfd * abfd)134 ppcboot_object_p (bfd *abfd)
135 {
136   struct stat statbuf;
137   asection *sec;
138   ppcboot_hdr_t hdr;
139   size_t i;
140   ppcboot_data_t *tdata;
141   flagword flags;
142 
143   BFD_ASSERT (sizeof (ppcboot_hdr_t) == 1024);
144 
145   if (abfd->target_defaulted)
146     {
147       bfd_set_error (bfd_error_wrong_format);
148       return NULL;
149     }
150 
151   /* Find the file size.  */
152   if (bfd_stat (abfd, &statbuf) < 0)
153     {
154       bfd_set_error (bfd_error_system_call);
155       return NULL;
156     }
157 
158   if ((size_t) statbuf.st_size < sizeof (ppcboot_hdr_t))
159     {
160       bfd_set_error (bfd_error_wrong_format);
161       return NULL;
162     }
163 
164   if (bfd_bread (&hdr, (bfd_size_type) sizeof (hdr), abfd)
165       != sizeof (hdr))
166     {
167       if (bfd_get_error () != bfd_error_system_call)
168 	bfd_set_error (bfd_error_wrong_format);
169 
170       return NULL;
171     }
172 
173   /* Now do some basic checks.  */
174   for (i = 0; i < sizeof (hdr.pc_compatibility); i++)
175     if (hdr.pc_compatibility[i])
176       {
177 	bfd_set_error (bfd_error_wrong_format);
178 	return NULL;
179       }
180 
181   if (hdr.signature[0] != SIGNATURE0 || hdr.signature[1] != SIGNATURE1)
182     {
183       bfd_set_error (bfd_error_wrong_format);
184       return NULL;
185     }
186 
187   if (hdr.partition[0].partition_end.ind != PPC_IND)
188     {
189       bfd_set_error (bfd_error_wrong_format);
190       return NULL;
191     }
192 
193   abfd->symcount = PPCBOOT_SYMS;
194 
195   /* One data section.  */
196   flags = SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_CODE | SEC_HAS_CONTENTS;
197   sec = bfd_make_section_with_flags (abfd, ".data", flags);
198   if (sec == NULL)
199     return NULL;
200   sec->vma = 0;
201   sec->size = statbuf.st_size - sizeof (ppcboot_hdr_t);
202   sec->filepos = sizeof (ppcboot_hdr_t);
203 
204   ppcboot_mkobject (abfd);
205   tdata = ppcboot_get_tdata (abfd);
206   tdata->sec = sec;
207   memcpy (&tdata->header, &hdr, sizeof (ppcboot_hdr_t));
208 
209   ppcboot_set_arch_mach (abfd, bfd_arch_powerpc, 0L);
210   return abfd->xvec;
211 }
212 
213 #define ppcboot_close_and_cleanup _bfd_generic_close_and_cleanup
214 #define ppcboot_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
215 #define ppcboot_new_section_hook _bfd_generic_new_section_hook
216 
217 
218 /* Get contents of the only section.  */
219 
220 static bfd_boolean
ppcboot_get_section_contents(bfd * abfd,asection * section ATTRIBUTE_UNUSED,void * location,file_ptr offset,bfd_size_type count)221 ppcboot_get_section_contents (bfd *abfd,
222 			      asection *section ATTRIBUTE_UNUSED,
223 			      void * location,
224 			      file_ptr offset,
225 			      bfd_size_type count)
226 {
227   if (bfd_seek (abfd, offset + (file_ptr) sizeof (ppcboot_hdr_t), SEEK_SET) != 0
228       || bfd_bread (location, count, abfd) != count)
229     return FALSE;
230   return TRUE;
231 }
232 
233 
234 /* Return the amount of memory needed to read the symbol table.  */
235 
236 static long
ppcboot_get_symtab_upper_bound(bfd * abfd ATTRIBUTE_UNUSED)237 ppcboot_get_symtab_upper_bound (bfd *abfd ATTRIBUTE_UNUSED)
238 {
239   return (PPCBOOT_SYMS + 1) * sizeof (asymbol *);
240 }
241 
242 
243 /* Create a symbol name based on the bfd's filename.  */
244 
245 static char *
mangle_name(bfd * abfd,char * suffix)246 mangle_name (bfd *abfd, char *suffix)
247 {
248   bfd_size_type size;
249   char *buf;
250   char *p;
251 
252   size = (strlen (bfd_get_filename (abfd))
253 	  + strlen (suffix)
254 	  + sizeof "_ppcboot__");
255 
256   buf = (char *) bfd_alloc (abfd, size);
257   if (buf == NULL)
258     return "";
259 
260   sprintf (buf, "_ppcboot_%s_%s", bfd_get_filename (abfd), suffix);
261 
262   /* Change any non-alphanumeric characters to underscores.  */
263   for (p = buf; *p; p++)
264     if (! ISALNUM (*p))
265       *p = '_';
266 
267   return buf;
268 }
269 
270 
271 /* Return the symbol table.  */
272 
273 static long
ppcboot_canonicalize_symtab(bfd * abfd,asymbol ** alocation)274 ppcboot_canonicalize_symtab (bfd *abfd, asymbol **alocation)
275 {
276   asection *sec = ppcboot_get_tdata (abfd)->sec;
277   asymbol *syms;
278   unsigned int i;
279   bfd_size_type amt = PPCBOOT_SYMS * sizeof (asymbol);
280 
281   syms = (asymbol *) bfd_alloc (abfd, amt);
282   if (syms == NULL)
283     return FALSE;
284 
285   /* Start symbol.  */
286   syms[0].the_bfd = abfd;
287   syms[0].name = mangle_name (abfd, "start");
288   syms[0].value = 0;
289   syms[0].flags = BSF_GLOBAL;
290   syms[0].section = sec;
291   syms[0].udata.p = NULL;
292 
293   /* End symbol.  */
294   syms[1].the_bfd = abfd;
295   syms[1].name = mangle_name (abfd, "end");
296   syms[1].value = sec->size;
297   syms[1].flags = BSF_GLOBAL;
298   syms[1].section = sec;
299   syms[1].udata.p = NULL;
300 
301   /* Size symbol.  */
302   syms[2].the_bfd = abfd;
303   syms[2].name = mangle_name (abfd, "size");
304   syms[2].value = sec->size;
305   syms[2].flags = BSF_GLOBAL;
306   syms[2].section = bfd_abs_section_ptr;
307   syms[2].udata.p = NULL;
308 
309   for (i = 0; i < PPCBOOT_SYMS; i++)
310     *alocation++ = syms++;
311   *alocation = NULL;
312 
313   return PPCBOOT_SYMS;
314 }
315 
316 #define ppcboot_make_empty_symbol _bfd_generic_make_empty_symbol
317 #define ppcboot_print_symbol _bfd_nosymbols_print_symbol
318 
319 /* Get information about a symbol.  */
320 
321 static void
ppcboot_get_symbol_info(bfd * ignore_abfd ATTRIBUTE_UNUSED,asymbol * symbol,symbol_info * ret)322 ppcboot_get_symbol_info (bfd *ignore_abfd ATTRIBUTE_UNUSED,
323 			 asymbol *symbol,
324 			 symbol_info *ret)
325 {
326   bfd_symbol_info (symbol, ret);
327 }
328 
329 #define ppcboot_get_symbol_version_string \
330   _bfd_nosymbols_get_symbol_version_string
331 #define ppcboot_bfd_is_target_special_symbol \
332   ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false)
333 #define ppcboot_bfd_is_local_label_name bfd_generic_is_local_label_name
334 #define ppcboot_get_lineno _bfd_nosymbols_get_lineno
335 #define ppcboot_find_nearest_line _bfd_nosymbols_find_nearest_line
336 #define ppcboot_find_line _bfd_nosymbols_find_line
337 #define ppcboot_find_inliner_info _bfd_nosymbols_find_inliner_info
338 #define ppcboot_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
339 #define ppcboot_read_minisymbols _bfd_generic_read_minisymbols
340 #define ppcboot_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
341 
342 /* Write section contents of a ppcboot file.  */
343 
344 static bfd_boolean
ppcboot_set_section_contents(bfd * abfd,asection * sec,const void * data,file_ptr offset,bfd_size_type size)345 ppcboot_set_section_contents (bfd *abfd,
346 			      asection *sec,
347 			      const void * data,
348 			      file_ptr offset,
349 			      bfd_size_type size)
350 {
351   if (! abfd->output_has_begun)
352     {
353       bfd_vma low;
354       asection *s;
355 
356       /* The lowest section VMA sets the virtual address of the start
357          of the file.  We use the set the file position of all the
358          sections.  */
359       low = abfd->sections->vma;
360       for (s = abfd->sections->next; s != NULL; s = s->next)
361 	if (s->vma < low)
362 	  low = s->vma;
363 
364       for (s = abfd->sections; s != NULL; s = s->next)
365 	s->filepos = s->vma - low;
366 
367       abfd->output_has_begun = TRUE;
368     }
369 
370   return _bfd_generic_set_section_contents (abfd, sec, data, offset, size);
371 }
372 
373 
374 static int
ppcboot_sizeof_headers(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)375 ppcboot_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED,
376 			struct bfd_link_info *info ATTRIBUTE_UNUSED)
377 {
378   return sizeof (ppcboot_hdr_t);
379 }
380 
381 
382 /* Print out the program headers.  */
383 
384 static bfd_boolean
ppcboot_bfd_print_private_bfd_data(bfd * abfd,void * farg)385 ppcboot_bfd_print_private_bfd_data (bfd *abfd, void * farg)
386 {
387   FILE *f = (FILE *)farg;
388   ppcboot_data_t *tdata = ppcboot_get_tdata (abfd);
389   long entry_offset = bfd_getl_signed_32 (tdata->header.entry_offset);
390   long length = bfd_getl_signed_32 (tdata->header.length);
391   int i;
392 
393   fprintf (f, _("\nppcboot header:\n"));
394   fprintf (f, _("Entry offset        = 0x%.8lx (%ld)\n"),
395 	   (unsigned long) entry_offset, entry_offset);
396   fprintf (f, _("Length              = 0x%.8lx (%ld)\n"),
397 	   (unsigned long) length, length);
398 
399   if (tdata->header.flags)
400     fprintf (f, _("Flag field          = 0x%.2x\n"), tdata->header.flags);
401 
402   if (tdata->header.os_id)
403     fprintf (f, "OS_ID               = 0x%.2x\n", tdata->header.os_id);
404 
405   if (tdata->header.partition_name[0])
406     fprintf (f, _("Partition name      = \"%s\"\n"), tdata->header.partition_name);
407 
408   for (i = 0; i < 4; i++)
409     {
410       long sector_begin  = bfd_getl_signed_32 (tdata->header.partition[i].sector_begin);
411       long sector_length = bfd_getl_signed_32 (tdata->header.partition[i].sector_length);
412 
413       /* Skip all 0 entries */
414       if (!tdata->header.partition[i].partition_begin.ind
415 	  && !tdata->header.partition[i].partition_begin.head
416 	  && !tdata->header.partition[i].partition_begin.sector
417 	  && !tdata->header.partition[i].partition_begin.cylinder
418 	  && !tdata->header.partition[i].partition_end.ind
419 	  && !tdata->header.partition[i].partition_end.head
420 	  && !tdata->header.partition[i].partition_end.sector
421 	  && !tdata->header.partition[i].partition_end.cylinder
422 	  && !sector_begin && !sector_length)
423 	continue;
424 
425       fprintf (f, _("\nPartition[%d] start  = { 0x%.2x, 0x%.2x, 0x%.2x, 0x%.2x }\n"), i,
426 	       tdata->header.partition[i].partition_begin.ind,
427 	       tdata->header.partition[i].partition_begin.head,
428 	       tdata->header.partition[i].partition_begin.sector,
429 	       tdata->header.partition[i].partition_begin.cylinder);
430 
431       fprintf (f, _("Partition[%d] end    = { 0x%.2x, 0x%.2x, 0x%.2x, 0x%.2x }\n"), i,
432 	       tdata->header.partition[i].partition_end.ind,
433 	       tdata->header.partition[i].partition_end.head,
434 	       tdata->header.partition[i].partition_end.sector,
435 	       tdata->header.partition[i].partition_end.cylinder);
436 
437       fprintf (f, _("Partition[%d] sector = 0x%.8lx (%ld)\n"),
438 	       i, (unsigned long) sector_begin, sector_begin);
439       fprintf (f, _("Partition[%d] length = 0x%.8lx (%ld)\n"),
440 	       i, (unsigned long) sector_length, sector_length);
441     }
442 
443   fprintf (f, "\n");
444   return TRUE;
445 }
446 
447 
448 #define ppcboot_bfd_get_relocated_section_contents \
449   bfd_generic_get_relocated_section_contents
450 #define ppcboot_bfd_relax_section bfd_generic_relax_section
451 #define ppcboot_bfd_gc_sections bfd_generic_gc_sections
452 #define ppcboot_bfd_lookup_section_flags bfd_generic_lookup_section_flags
453 #define ppcboot_bfd_merge_sections bfd_generic_merge_sections
454 #define ppcboot_bfd_is_group_section bfd_generic_is_group_section
455 #define ppcboot_bfd_discard_group bfd_generic_discard_group
456 #define ppcboot_section_already_linked \
457   _bfd_generic_section_already_linked
458 #define ppcboot_bfd_define_common_symbol bfd_generic_define_common_symbol
459 #define ppcboot_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
460 #define ppcboot_bfd_link_add_symbols _bfd_generic_link_add_symbols
461 #define ppcboot_bfd_link_just_syms _bfd_generic_link_just_syms
462 #define ppcboot_bfd_copy_link_hash_symbol_type \
463   _bfd_generic_copy_link_hash_symbol_type
464 #define ppcboot_bfd_final_link _bfd_generic_final_link
465 #define ppcboot_bfd_link_split_section _bfd_generic_link_split_section
466 #define ppcboot_get_section_contents_in_window \
467   _bfd_generic_get_section_contents_in_window
468 #define ppcboot_bfd_link_check_relocs _bfd_generic_link_check_relocs
469 
470 #define ppcboot_bfd_copy_private_bfd_data _bfd_generic_bfd_copy_private_bfd_data
471 #define ppcboot_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data
472 #define ppcboot_bfd_copy_private_section_data _bfd_generic_bfd_copy_private_section_data
473 #define ppcboot_bfd_copy_private_symbol_data _bfd_generic_bfd_copy_private_symbol_data
474 #define ppcboot_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data
475 #define ppcboot_bfd_set_private_flags _bfd_generic_bfd_set_private_flags
476 #define ppcboot_bfd_print_private_bfd_dat ppcboot_bfd_print_private_bfd_data
477 
478 const bfd_target powerpc_boot_vec =
479 {
480   "ppcboot",			/* name */
481   bfd_target_unknown_flavour,	/* flavour */
482   BFD_ENDIAN_BIG,		/* byteorder is big endian for code */
483   BFD_ENDIAN_LITTLE,		/* header_byteorder */
484   EXEC_P,			/* object_flags */
485   (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE | SEC_DATA
486    | SEC_ROM | SEC_HAS_CONTENTS), /* section_flags */
487   0,				/* symbol_leading_char */
488   ' ',				/* ar_pad_char */
489   16,				/* ar_max_namelen */
490   0,				/* match priority.  */
491   bfd_getb64, bfd_getb_signed_64, bfd_putb64,
492   bfd_getb32, bfd_getb_signed_32, bfd_putb32,
493   bfd_getb16, bfd_getb_signed_16, bfd_putb16,	/* data */
494   bfd_getl64, bfd_getl_signed_64, bfd_putl64,
495   bfd_getl32, bfd_getl_signed_32, bfd_putl32,
496   bfd_getl16, bfd_getl_signed_16, bfd_putl16,	/* hdrs */
497   {				/* bfd_check_format */
498     _bfd_dummy_target,
499     ppcboot_object_p,		/* bfd_check_format */
500     _bfd_dummy_target,
501     _bfd_dummy_target,
502   },
503   {				/* bfd_set_format */
504     bfd_false,
505     ppcboot_mkobject,
506     bfd_false,
507     bfd_false,
508   },
509   {				/* bfd_write_contents */
510     bfd_false,
511     bfd_true,
512     bfd_false,
513     bfd_false,
514   },
515 
516   BFD_JUMP_TABLE_GENERIC (ppcboot),
517   BFD_JUMP_TABLE_COPY (ppcboot),
518   BFD_JUMP_TABLE_CORE (_bfd_nocore),
519   BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
520   BFD_JUMP_TABLE_SYMBOLS (ppcboot),
521   BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
522   BFD_JUMP_TABLE_WRITE (ppcboot),
523   BFD_JUMP_TABLE_LINK (ppcboot),
524   BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
525 
526   NULL,
527 
528   NULL
529 };
530